Add inline example for nearneighbor (#1919)

Co-authored-by: Dongdong Tian <seisman.info@gmail.com>

pygmt/src/nearneighbor.py

@@ -12,6 +12,8 @@
 )
 from pygmt.io import load_dataarray
 
+__doctest_skip__ = ["nearneighbor"]
+
 
 @fmt_docstring
 @use_alias(
@@ -131,6 +133,19 @@ def nearneighbor(data=None, x=None, y=None, z=None, **kwargs):
         - :class:`xarray.DataArray`: if ``outgrid`` is not set
         - None if ``outgrid`` is set (grid output will be stored in file set by
           ``outgrid``)
+    Example
+    -------
+    >>> import pygmt
+    >>> # Load a sample dataset of bathymetric x, y, and z values
+    >>> data = pygmt.datasets.load_sample_data(name="bathymetry")
+    >>> # Create a new grid with 5 arc-minute spacing in the designated region
+    >>> # Set search_radius to only consider points within 10 arc-minute of a node
+    >>> output = pygmt.nearneighbor(
+    ...     data=data,
+    ...     spacing="5m",
+    ...     region=[245, 255, 20, 30],
+    ...     search_radius="10m",
+    ... )
     """
     with GMTTempFile(suffix=".nc") as tmpfile:
         with Session() as lib: